Accuracy of Distal Femoral Valgus Deformity Correction: Fixator-Assisted Nailing vs Fixator-Assisted Locked Plating.

Abstract

Fixator-assisted nailing (FAN) and fixator-assisted locked plating (FALP) are 2 techniques that can be used to correct distal femoral valgus deformities. The fixator aids in achieving an accurate adjustable initial reduction, which is then made permanent with either nail or plate insertion. FALP can be performed with the knee held in a neutral extended position, whereas FAN requires 30° to 90° of knee flexion to insert the nail, which may cause some alignment loss. We hypothesized that FAN may yield less accurate correction than FALP. Prospectively collected data of a consecutive cohort of patients who underwent valgus deformity femoral correction with FAN or FALP at a single institution over an 8-year period were retrospectively evaluated. Twenty extremities (18 patients) were treated using FAN (median follow-up, 5 years; range, 1-10 years), and 7 extremities (6 patients) were treated with FALP (median follow-up, 5 years; range, 1-8 years). In the FAN cohort, the mean preoperative and postoperative mechanical lateral distal femoral angles (mLDFAs) were 81° (range, 67°-86°) and 89° (range, 80°-100°), respectively (P = .009). In the FALP cohort, the mean preoperative and postoperative mLDFAs were 80° (range, 71°-87°) and 88° (range, 81°-94°), respectively (P < .001). Although the average mechanical axis deviation correction for the FALP group was greater than for the FAN group (32 mm and 27 mm, respectively), the difference was not significant (P = .66). Both methods of femoral deformity correction can be considered safe and effective. On the basis of our results, FAN and FALP are comparable in accuracy for deformity correction in the distal femur.